/**
* NAME=1的选择性显然比SCHOOL>1好，所以选择二级索引NAME
*
* @throws QueryException
*/
@Test
public void testChooseIndex列出现的顺序不影响索引选择() throws QueryException {
TableNode table1 = new TableNode("TABLE1");
QueryTreeNode qn1 = table1.query("SCHOOL>1&&NAME=1");
qn1.build();
IndexMeta index =
IndexChooser.findBestIndex(
table1.getTableMeta(),
table1.getColumnsRefered(),
toDNFFilter(table1.getWhereFilter()),
table1.getTableName(),
extraCmd);
Assert.assertNotNull(index);
Assert.assertEquals(index.getName(), "TABLE1._NAME");
TableNode table2 = new TableNode("TABLE1");
QueryTreeNode qn2 = table2.query("NAME=1&&SCHOOL>1");
qn2.build();
index =
IndexChooser.findBestIndex(
table2.getTableMeta(),
table2.getColumnsRefered(),
toDNFFilter(table2.getWhereFilter()),
table2.getTableName(),
extraCmd);
Assert.assertNotNull(index);
Assert.assertEquals(index.getName(), "TABLE1._NAME");
}
/** 虽然C1，C2上存在组合索引，但是由于范围查询的选择度不如等值查询 因此还是选择了单索引NAME=1 */
@Test
public void testChooseIndex单索引选择度好于组合索引() throws QueryException {
TableNode table = new TableNode("TABLE9");
QueryTreeNode qn = table.query("C1>10&&C2>3&&NAME=1");
qn.build();
IndexMeta index =
IndexChooser.findBestIndex(
table.getTableMeta(),
table.getColumnsRefered(),
toDNFFilter(table.getWhereFilter()),
table.getTableName(),
extraCmd);
Assert.assertNotNull(index);
Assert.assertEquals(index.getName(), "TABLE9._NAME");
}
@Test
public void testChooseIndex() throws QueryException {
TableNode table = new TableNode("TABLE1");
QueryTreeNode qn = table.query("ID=1");
qn.build();
IndexMeta index =
IndexChooser.findBestIndex(
table.getTableMeta(),
emptyColumns,
toDNFFilter(table.getWhereFilter()),
table.getTableName(),
extraCmd);
Assert.assertNotNull(index);
Assert.assertEquals(index.getName(), "TABLE1");
}
/** C6,C7同时存在组合索引和倒排索引 同时有倒排和组合索引，并且选择度一样，优先选择组合 */
@Test
public void testChooseIndex选择度相同优先选组合() throws QueryException {
TableNode table = new TableNode("TABLE9");
QueryTreeNode qn = table.query("C6=10&&C7=3");
qn.build();
IndexMeta index =
IndexChooser.findBestIndex(
table.getTableMeta(),
table.getColumnsRefered(),
toDNFFilter(table.getWhereFilter()),
table.getTableName(),
extraCmd);
Assert.assertNotNull(index);
Assert.assertEquals(index.getName(), "TABLE9._C6_C7");
}